HWKey (19) - all important reaction intermediates If a...

Problem of the Day #18 – Answer Key Deadline : 3:00 p.m., Tuesday, 7/8/08 LATE WORK WILL NOT BE ACCEPTED OR GRADED!!! This problem is worth a total of 20 raw points. When enantiomerically pure ( S )-3-bromo-2-methylpentane is heated to 60°C in a mixture of H 2 O/acetone, 2-methyl-2-pentanol (achiral) is eventually isolated as the major organic product. This overall transformation is shown below: Br ( S )-3-Bromo-2-methylpentane H 2 O/acetone 60°C OH + H 3 O + Br 2-Methyl-2-pentanol (a) (15 points) Propose a reaction mechanism to account for the overall transformation shown above. As usual, use curved arrows to show movement of electron pairs, and be sure to show structures of

This is the end of the preview.
Sign up
to
access the rest of the document.

Unformatted text preview: all important reaction intermediates. If a reaction intermediate is a resonance hybrid, it is only necessary to draw the most important contributing resonance structure. [ Note : The acetone is necessary to dissolve the alkyl bromide starting material. Acetone DOES NOT play any role whatsoever in the reaction mechanism!!!] (b) (5 points) Is the mechanism you proposed above best described as an example of an S N 1 reaction, or is it an example of an S N 2 reaction? Circle your choice below. No additional explanation is required. S N 1 S N 2 Br H Br (hydride shift) H O H H O H H Br O H H OH O H H H Br Br...
View
Full Document